## the basic editor data structure, and how it displays text to the screen # temporary main for this layer: just render the given text at the given # screen dimensions, then stop def! main text:text [ local-scope load-ingredients open-console hide-screen 0/screen e:&:editor <- new-editor text, 0/left, 5/right render 0/screen, e show-screen 0/screen wait-for-event 0/console close-console ] scenario editor-renders-text-to-screen [ local-scope assume-screen 10/width, 5/height e:&:editor <- new-editor [abc], 0/left, 10/right run [ render screen, e ] screen-should-contain [ # top line of screen reserved for menu . . .abc . . . ] ] container editor [ # editable text: doubly linked list of characters (head contains a special sentinel) data:&:duplex-list:char top-of-screen:&:duplex-list:char bottom-of-screen:&:duplex-list:char # location before cursor inside data before-cursor:&:duplex-list:char # raw bounds of display area on screen # always displays from row 1 (leaving row 0 for a menu) and at most until bottom of screen left:num right:num bottom:num # raw screen coordinates of cursor cursor-row:num cursor-column:num ] # creates a new editor widget # right is exclusive def new-editor s:text, left:num, right:num -> result:&:editor [ local-scope load-ingredients # no clipping of bounds right <- subtract right, 1 result <- new editor:type # initialize screen-related fields *result <- put *result, left:offset, left *result <- put *result, right:offset, right # initialize cursor coordinates *result <- put *result, cursor-row:offset, 1/top *result <- put *result, cursor-column:offset, left # initialize empty contents init:&:duplex-list:char <- push 167/§, 0/tail *result <- put *result, data:offset, init *result <- put *result, top-of-screen:offset, init *result <- put *result, before-cursor:offset, init result <- insert-text result, s ] def insert-text editor:&:editor, text:text -> editor:&:editor [ local-scope load-ingredients # early exit if text is empty return-unless text len:num <- length *text return-unless len idx:num <- copy 0 # now we can start appending the rest, character by character curr:&:duplex-list:char <- get *editor, data:offset { done?:bool <- greater-or-equal idx, len break-if done? c:char <- index *text, idx insert c, curr # next iter curr <- next curr idx <- add idx, 1 loop } ] scenario editor-initializes-without-data [ local-scope assume-screen 5/width, 3/height run [ e:&:editor <- new-editor 0/data, 2/left, 5/right 2:editor/raw <- copy *e ] memory-should-contain [ # 2 (data) <- just the § sentinel # 3 (top of screen) <- the § sentinel 4 <- 0 # bottom-of-screen; null since text fits on screen # 5 (before cursor) <- the § sentinel 6 <- 2 # left 7 <- 4 # right (inclusive) 8 <- 0 # bottom (not set until render) 9 <- 1 # cursor row 10 <- 2 # cursor column ] screen-should-contain [ . . . . . . ] ] # Assumes cursor should be at coordinates (cursor-row, cursor-column) and # updates before-cursor to match. Might also move coordinates if they're # outside text. def render screen:&:screen, editor:&:editor -> last-row:num, last-column:num, screen:&:screen, editor:&:editor [ local-scope load-ingredients return-unless editor, 1/top, 0/left left:num <- get *editor, left:offset screen-height:num <- screen-height screen right:num <- get *editor, right:offset # traversing editor curr:&:duplex-list:char <- get *editor, top-of-screen:offset prev:&:duplex-list:char <- copy curr # just in case curr becomes null and we can't compute prev curr <- next curr # traversing screen +render-loop-initialization color:num <- copy 7/white row:num <- copy 1/top column:num <- copy left cursor-row:num <- get *editor, cursor-row:offset cursor-column:num <- get *editor, cursor-column:offset before-cursor:&:duplex-list:char <- get *editor, before-cursor:offset screen <- move-cursor screen, row, column { +next-character break-unless curr off-screen?:bool <- greater-or-equal row, screen-height break-if off-screen? # update editor.before-cursor # Doing so at the start of each iteration ensures it stays one step behind # the current character. { at-cursor-row?:bool <- equal row, cursor-row break-unless at-cursor-row? at-cursor?:bool <- equal column, cursor-column break-unless at-cursor? before-cursor <- copy prev } c:char <- get *curr, value:offset { # newline? move to left rather than 0 newline?:bool <- equal c, 10/newline break-unless newline? # adjust cursor if necessary { at-cursor-row?:bool <- equal row, cursor-row break-unless at-cursor-row? left-of-cursor?:bool <- lesser-than column, cursor-column break-unless left-of-cursor? cursor-column <- copy column before-cursor <- prev curr } # clear rest of line in this window clear-line-until screen, right # skip to next line row <- add row, 1 column <- copy left screen <- move-cursor screen, row, column curr <- next curr prev <- next prev loop +next-character } { # at right? wrap. even if there's only one more letter left; we need # room for clicking on the cursor after it. at-right?:bool <- equal column, right break-unless at-right? # print wrap icon wrap-icon:char <- copy 8617/loop-back-to-left print screen, wrap-icon, 245/grey column <- copy left row <- add row, 1 screen <- move-cursor screen, row, column # don't increment curr loop +next-character } print screen, c, color curr <- next curr prev <- next prev column <- add column, 1 loop } # save first character off-screen *editor <- put *editor, bottom-of-screen:offset, curr # is cursor to the right of the last line? move to end { at-cursor-row?:bool <- equal row, cursor-row cursor-outside-line?:bool <- lesser-or-equal column, cursor-column before-cursor-on-same-line?:bool <- and at-cursor-row?, cursor-outside-line? above-cursor-row?:bool <- lesser-than row, cursor-row before-cursor?:bool <- or before-cursor-on-same-line?, above-cursor-row? break-unless before-cursor? cursor-row <- copy row cursor-column <- copy column before-cursor <- copy prev } *editor <- put *editor, bottom:offset, row *editor <- put *editor, cursor-row:offset, cursor-row *editor <- put *editor, cursor-column:offset, cursor-column *editor <- put *editor, before-cursor:offset, before-cursor return row, column ] def clear-screen-from screen:&:screen, row:num, column:num, left:num, right:num -> screen:&:screen [ local-scope load-ingredients # if it's the real screen, use the optimized primitive { break-if screen clear-display-from row, column, left, right return } # if not, go the slower route screen <- move-cursor screen, row, column clear-line-until screen, right clear-rest-of-screen screen, row, left, right ] def clear-rest-of-screen screen:&:screen, row:num, left:num, right:num -> screen:&:screen [ local-scope load-ingredients row <- add row, 1 screen <- move-cursor screen, row, left screen-height:num <- screen-height screen { at-bottom-of-screen?:bool <- greater-or-equal row, screen-height break-if at-bottom-of-screen? screen <- move-cursor screen, row, left clear-line-until screen, right row <- add row, 1 loop } ] scenario editor-prints-multiple-lines [ local-scope assume-screen 5/width, 5/height s:text <- new [abc def] e:&:editor <- new-editor s, 0/left, 5/right run [ render screen, e ] screen-should-contain [ . . .abc . .def . . . ] ] scenario editor-handles-offsets [ local-scope assume-screen 5/width, 5/height e:&:editor <- new-editor [abc], 1/left, 5/right run [ render screen, e ] screen-should-contain [ . . . abc . . . ] ] scenario editor-prints-multiple-lines-at-offset [ local-scope assume-screen 5/width, 5/height s:text <- new [abc def] e:&:editor <- new-editor s, 1/left, 5/right run [ render screen, e ] screen-should-contain [ . . . abc . . def . . . ] ] scenario editor-wraps-long-lines [ local-scope assume-screen 5/width, 5/height e:&:editor <- new-editor [abc def], 0/left, 5/right run [ render screen, e ] screen-should-contain [ . . .abc ↩. .def . . . ] screen-should-contain-in-color 245/grey [ . . . ↩. . . . . ] ] scenario editor-wraps-barely-long-lines [ local-scope assume-screen 5/width, 5/height e:&:editor <- new-editor [abcde], 0/left, 5/right run [ render screen, e ] # still wrap, even though the line would fit. We need room to click on the # end of the line screen-should-contain [ . . .abcd↩. .e . . . ] screen-should-contain-in-color 245/grey [ . . . ↩. . . . . ] ] scenario editor-with-empty-text [ local-scope assume-screen 5/width, 5/height e:&:editor <- new-editor [], 0/left, 5/right run [ render screen, e 3:num/raw <- get *e, cursor-row:offset 4:num/raw <- get *e, cursor-column:offset ] screen-should-contain [ . . . . . . ] memory-should-contain [ 3 <- 1 # cursor row 4 <- 0 # cursor column ] ] # just a little color for Mu code scenario render-colors-comments [ local-scope assume-screen 5/width, 5/height s:text <- new [abc # de f] e:&:editor <- new-editor s, 0/left, 5/right run [ render screen, e ] screen-should-contain [ . . .abc . .# de . .f . . . ] screen-should-contain-in-color 12/lightblue, [ . . . . .# de . . . . . ] screen-should-contain-in-color 7/white, [ . . .abc . . . .f . . . ] ] after [ color <- get-color color, c ] # so far the previous color is all the information we need; that may change def get-color color:num, c:char -> color:num [ local-scope load-ingredients color-is-white?:bool <- equal color, 7/white # if color is white and next character is '#', switch color to blue { break-unless color-is-white? starting-comment?:bool <- equal c, 35/# break-unless starting-comment? trace 90, [app], [switch color back to blue] color <- copy 12/lightblue jump +exit } # if color is blue and next character is newline, switch color to white { color-is-blue?:bool <- equal color, 12/lightblue break-unless color-is-blue? ending-comment?:bool <- equal c, 10/newline break-unless ending-comment? trace 90, [app], [switch color back to white] color <- copy 7/white jump +exit } # if color is white (no comments) and next character is '<', switch color to red { break-unless color-is-white? starting-assignment?:bool <- equal c, 60/< break-unless starting-assignment? color <- copy 1/red jump +exit } # if color is red and next character is space, switch color to white { color-is-red?:bool <- equal color, 1/red break-unless color-is-red? ending-assignment?:bool <- equal c, 32/space break-unless ending-assignment? color <- copy 7/white jump +exit } # otherwise no change +exit return color ] scenario render-colors-assignment [ local-scope assume-screen 8/width, 5/height s:text <- new [abc d <- e f] e:&:editor <- new-editor s, 0/left, 8/right run [ render screen, e ] screen-should-contain [ . . .abc . .d <- e . .f . . . ] screen-should-contain-in-color 1/red, [ . . . . . <- . . . . . ] ]